Andy Burnham has sought advice from Sue Gray, Keir Starmer’s former chief of staff, on how to manage a potential transition into Downing Street if he returns to Westminster and succeeds the prime minister.

Lady Gray is understood to have advised Burnham on how a future government could be formed as Labour’s internal succession chatter intensifies before the Makerfield byelection.

The discussions highlight how seriously senior Labour figures are treating Burnham’s path back to Westminster, after weeks of speculation surrounding Starmer’s long-term future after a bruising set of local election results.

Burnham and Gray are understood to have known one another for decades, going back to his time as a minister within Tony Blair’s government while Gray was in the Cabinet Office. It is understood that Gray is not expected to take any formal role in a future government.

Gray resigned from Downing Street in October 2024, after hostile briefings and tensions within Starmer’s operation over her role. Gray was accused of alienating some of her political colleagues, who accused her of “control freakery”, and creating a bottleneck in No 10 that delayed policy decisions and appointments.

Allies of Burnham said he remained focused on the Makerfield byelection, likely to be a pivotal moment for the Labour party’s future direction and Burnham’s political trajectory.

Darren Jones, the chief secretary to the prime minister, criticised the internal jockeying, telling the BBC’s Sunday with Laura Kuenssberg show: “There’s a lot of fantasy politics going on right now inside the Labour party … in terms of who is up, who is down, who will be in what position.”

He said a debate inside the Labour party had “to happen off the back of bad local election results”, but that must not distract from “our primary focus on the country”.

Jones said: “I’m all up for having a debate inside the Labour party about how we improve our electoral performance in the years ahead, because we don’t want to hand the country to Reform.”

Jones, a senior ally of Starmer, called Burnham a “brilliant politician” and confirmed he would be campaigning for him in Makerfield.

But he added: “Irrespective of individual ambitions from any of my colleagues, the big questions the country faces are still the big questions the country faces. There’s no magic answer to any of them, because if there was we would have implemented it.”

The pressure on Labour has intensified with a Survation survey published this week showing Labour remained on course to win the seat, with Reform UK running very close in what would have once been considered safe Labour territory. The polling put Burnham for Labour on 43%, with Robert Kenyon for Reform UK on 40%.

A More in Common survey published last week put Labour on 30% nationally under Burnham’s leadership, only slightly ahead of Reform UK on 27% and the Tories on 20%.

Senior Labour figures have been pictured rallying support for Burnham’s campaign in Makerfield. Wes Streeting, widely viewed as a potential rival contender in any future leadership race, campaigned for Burnham over the weekend, alongside Labour’s deputy leader Lucy Powell. The chief whip Jonathan Reynolds, still seen as an ally of Starmer, was also spotted holding a Burnham for Makerfield poster last week.

The show of support comes after Streeting sought to position himself while setting out his own vision for Labour’s future. The former health secretary has argued for a “wealth tax that works” and also called for a “proper contest” over Labour’s direction, insisting he could win a future leadership contest.

Over the past week, Burnham has continued to distance himself from calls for Britain to rejoin the EU – a stance he has repeated since the last Labour conference, and argued for greater public control over transport, housing and energy.

The former foreign secretary David Miliband told the Hay literary festival on Saturday that Labour needed to “get on to the pitch”, and that there hadn’t been enough change during Starmer’s prime ministership. While the government had “done a lot of good things” regarding apprenticeships, breakfast clubs, renewable energy and welfare-to-work, they all needed to be “five times or 10 times what they’ve been done”, he added.

“If those who are arguing to change the prime minister don’t change the policy, nothing will be different,” Miliband continued, adding that the “what” matters more than the “who”. He said a “mistake” of the government had been giving the impression that it spent “all its time thinking about a vote in three years’ time”.

Asked about reports that his brother, Ed, may be appointed chancellor if Burnham makes it to No 10, David Miliband said: “It’s not something I’ve discussed with him, and even if I had, I wouldn’t be talking about it with you.”